Clinically significant fatigue was associated with increased inflammation in breast cancer survivors, according to study findings published in BMC Women's Health. The study authors also suggested that an increase in inflammatory markers from clinical fatigue could lead to breast cancer recurrence.
“Studying inflammation in breast cancer survivors is important because past research has shown a link between inflammation and cancer progression or recurrence,” stated lead study author Ali A. Weinstein, PhD, Professor, Global and Community Health, and Senior Scholar, Center for the Advancement of Well-Being, George Mason University College of Public Health. “Fatigue can also strongly influence survivors’ daily quality of life, and we suspect it may be connected to inflammation. We’re working to better understand that connection, particularly with short-term exposures that may accumulate—and increase inflammation—over time.”
Study Methods and Rationale
The researchers conducted a pilot study of responses to physically and mentally tiring tasks completed by breast cancer survivors to measure changes in inflammatory cytokines and fatigue.
They recruited 46 women who were breast cancer survivors, and these women were randomly assigned to three groups looking at exposure to physical fatigue, mental fatigue, or the control group. In the physical fatigue group, participants completed a 6-minute walking or running test. In the mental fatigue group, participants performed a dual 2-back computer task. In the control group, participants watched a nature video for 6 minutes.
Using the Bio-Plex 200 Suspension Array System, researchers looked at serum levels of IL-1β, IL-4, IL-5, IL-6, IL-8, IL-10, eotaxin, TNF-α, TGF-β1, and VEGF as indicators of inflammation related to immune function, stress, and mood. These samples were collected before the tasks, immediately after, and again after a 30-minute recovery period.
Key Study Findings
The study did not find many statistically significant changes in inflammatory markers in response to the short fatigue-inducing tasks in the interventional groups.
However, levels of TGF-β and eotaxin were consistently changed showing responses to fatigue-inducing tasks, especially in patients with clinical fatigue.
The study authors concluded that "acute fatigue challenges, the kind that [breast cancer survivors] would be exposed to in everyday circumstances, does increase inflammatory responses, and those with clinically significant levels of fatigue at baseline are more likely to show these effects."
Disclosure: The study was funded by a grant from the PNC Charitable Trust. For full disclosures of the study authors, visit link.springer.com.
